• Journal of Microbiology and Biotechnology
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• v.24 no.10
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• pp.1389-1396
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• 2014

The entire nucleotide sequence of the TKL1 gene encoding transketolase (TKL) in an erythritol-producing yeast of Candida magnoliae was determined by degenerate polymerase chain reaction and genome walking. Sequence analysis revealed an open reading frame of C. magnoliae TKL1 (CmTKL1) that spans 2,088 bp and encodes 696 amino acids, sharing 61.7% amino acid identity to Kluyveromyces lactis TKL. Functional analysis showed that CmTKL1 complemented a Saccharomyces cerevisiae tkl1 tkl2 double mutant for growth in the absence of aromatic amino acids and restored transketolase activity in this mutant. An enzyme activity assay and RT-PCR revealed that the expression of CmTKL1 is induced by fructose, $H_2O_2$, and KCl. The GenBank accession number for C. magnoliae TKL1 is KF751756.

• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3738-3742
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• 2011

Bismuth tribromide ($BiBr_3$) catalyzed Mannich-type reactions of N-acyliminium ions which generated in situ from N-benzyloxycarbonylamino p-tolylsulfones have been developed. In the presence of catalytic amount of $BiBr_3$, N-benzyloxycarbonylamino p-tolylsulfones prepared from aromatic and aliphatic aldehydes reacted with silyl enol ether and silyl enol ester under mild reaction conditions to afford N-Cbz-protected ${\beta}$-amino ketones and N-Cbz-protected ${\beta}$-amino esters in moderate to good yield, respectively.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.48-54
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• 2008

A putative ${\omega}$-aminotransferase gene, cc3143 (aptA), from Caulobacter crescentus was screened by bioinformatical tools and overexpressed in E. coli, and the substrate specificity of the ${\omega}$-aminotransferase was investigated. AptA showed high activity for short-chain ${\beta}$-amino acids. It showed the highest activity for 3-amino-n-butyric acid. It showed higher activity toward aromatic amines than aliphatic amines. The 3D model of the ${\omega}$-aminotransferase was constructed by homology modeling using a dialkylglycine decarboxylase (PDB ID: 1DGE) as a template. Then, the ${\omega}$-aminotransferase was rationally redesigned to increase the activity for 3-amino-3-phenylpropionic acid. The mutants N285A and V227G increased the relative activity for 3-amino-3-phenylpropionic acid to 3-amino-n-butyric acid by 11-fold and 3-fold, respectively, over that of wild type.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.4
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• pp.496-504
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• 1996

The study was conducted to obtain the basic information on increasing aromatic degrees by shading and organic matter application on Condonopsis lanceolata. The result were as followings : Fresh root wt. in shading 55 % treatment was increased about twices, whereas fresh root weight in non-shading was decreased. But growth of ground parts such as vine length, leaf width, and leaf number was promoted under non-shading treatment. Macroelements such as K, Ca, and Mg, were increased in non-shading and higher organic matter application. The components such as crude protein, fiber, and ash were increased in the shading 55% treatment compared with non-shading. In the sixteen amino acids, arginine contents were the highest in non-shading and organic matter 30M/T. Recovery yield of essential oil was 0.005% in non-shading. The highest was organic matter 30M/T in the non-shading as 0.007%. Major aromatic constituents were 11 kinds of aliphatic alcohols such as I-hexanol, cis-3-hexenol, and trans-2-hexanal. As a result, major aromatic degree was higher in shading 55%, also increased in the much organic matter application. It was considered to be applied dense shading 55% and much organic matters to produce Condonopsis lanceolata plants which have high aroma and good quality.

• The Korean Journal of Zoology
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• v.39 no.3
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• pp.307-316
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• 1996

A persistent major haemolyruph protein (MHP) was confirmed, and its ontogeny and physicochemical charadedstics were investigated in Helicoverpa assulta. The MHP existed continually during larval-pupal-adult development, and its ontogeny was similar to that of total haemolymph protein concentration during development. Its content increased with larval growth, and kept to high level during pupal-adult development except for temporary decrease at the early pupal and adult stages. The MHP was purified by ammonium sulfate precipitation, gel filtration and ion exchange chromatography. The purified MHP was determined to be hexamer glycolipoprotein (pI 5.9, M.W. 414kDa) consisted of single type subunit (69kDa). Amino acid analysis suggested that the MHP contained a relatively high content of aromatic amino acids (18.27 mole % of tryptophan, 7.47 mole % of tyrosine and 6.51 mole % of phenylalanine) compared to storage proteins from other insects. Immunodiffusion test and electrophoretic analysis of the organ proteins (gut, fat body, and Malphigian tubule) suggested that the major haemolymph protein was present in the fat body.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.964-971
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• 1995

Volatile flavor compounds and free amino acids in untreated and hydrolysate pen shell by-product produced with APL 440 protease were compared by vacuum simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry. A total of 109 volatile flavor compounds were detected in hydrolysate (65 compounds) or the 109 volatile flavor compounds were detected in untreated pen shell by-product (88). These compounds were composed of aldehydes(16), ketones(17), alcohols(31), nitrogen containing compounds (16), aromatic hydrocarbon compounds(8), esters(3), and miscellaneous compounds (17). Levels of aldehydes and aromatic hydrocarbons decreased after hydrolysis, whereas levels of nitrogen containing compounds increased 3 times than in untreated pen shell by-product. Taurine, known to be having a physiological function, was accounted for 31.25% of total amino acids in hydrolysate.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.247-251
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• 1997

Effects of amino acids on the lactic acid bacteria in kimchi were studied. 73 different lactic acid bacteria have been isolated during the kimchi fermentation at $15^{\circ}C$. Among these bacteria, dextran formers were occupied by 69.9%, of which Leuconostoc and Lactobacillus were 4.1% and 65.8%, respectively. All isolates didn't grow in a medium added with 500 ppm of tyrosine, whereas such an inhibition was not exhibited in kimchi with the same concentration of tyrosine. In kimchi added with tyrosine the lactic acid bacteria were less diverse than in the natural kimchi but the ratio of dextran formers were similar. As contrasted with natural kimchi, Leuconostoc was rather increased up to 41.4% and Lactobacillus was decreased down to 29.3%. Dominant species in each genus were Leu. mesenteroides and Lac. minor. Thus it is believed that tyrosine had inhibition effect for the growth of most Lactobacillus in kimchi.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.11a
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• pp.21-28
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• 2001

A newly isolated Aspergillus niger possessing the novel epoxide hydrolase(EHase) activity was investigated for the enantioselective hydrolysis of racemic aromatic epoxides. The gene encoding EHase was cloned by RT-PCR, and molecular characteristics of the EHase gene were compared with other microbial EHases. The cloned gene encodes 398 amino acids with a deduced molecular mass of 44.5 kDa and pI of 4.83, and sequence homology with other microbial EHase was low. Functional recombinant EHase could be obtained by heterologous expressions in E. coli. Enantioselectivity of recombinant EHase was tested for valuable aromatic epoxide intermediates. Reaction conditions of EHase-catalyzed asymmetric resolution were optimized for the production of chiral styrene oxide.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.227-232
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• 1990

The effects of alachlor [2-chloro-2', 6' diethyl-N-(methoxymethyl) acetanilide] treatment on nucleic acid, amino acid and protein synthesis were studied. The amide herbicide alachlor blocks the biosynthesis of the amino acids isoleucine, valine and aromatic amino acid in oat root tips. Nucleic acid was inhibited, but was not proportional to reduction in protein synthesis. $1{\times}10^{-4}M$ of alachlor treatment of oat roots inhibited 36% DNA synthesis, but DNA synthesis was not inhibited at $1{\times}10^{-5}M$. RNA synthesis was inhibited by $1{\times}10^{-5}M$ and $1{\times}10^{-4}M$ of alachlor 16 and 27%, respectively, while inhibition of protein synthesis did occur at same concentrations. Inhibition of protein synthesis also did not occur at concentration below $1{\times}10^{-4}M$ alachlor. It suggest that inhibition of protein sythesis caused significantly by alachlor($1{\times}l0^{-3}M$) result from secondary action.

• Journal of Microbiology and Biotechnology
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• v.11 no.4
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• pp.668-676
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• 2001

Pseudomonas sp. strain SY5 is a PCB-degrading bacterium [24] that includes two different enzymes (BphC1 and BphC2) encoding 2,3-dihdroxybiphenyl 1,2-dioxygenase and BphD encoding 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase. The bphC1 and bphC2 genes were found to consist of 897 based encoding 299 amino acids and 882 bases encoding 294 amino acids, respectively, whereas the bphD gene consisted of 861 bases encoding 287 amino acids. According to a homology search, a 50% and 39% similarity between the bphC1 and bphC2 genes at the nucleotide and amino acid level was shown, respectively. The bphC1 gene showed a 38% and 45% similarity at the amino acid level to Alcaligenes eutrophus A5 and Rhodococcus rhodochrous, respectively, whereas, bphC2 showed a 95% and 43% similarity, respectively. A comparison of the deduced amino acid sequence of the bphD product of Pseudomonas sp. SY5 with that of A. eutrophus A5, Pseudomons sp. KKS102, and LB400 showed a sequence identity of 92, 92, and 79%, respectively. Strain SY5 was originally isolated from municipal sewage containing recalcitrant organic compounds an found to have a high degradability of various aromatic compounds [23]. The current study found that strain SY5 had two extradiol-type dioxygenases, which did not hybridize with each other as they had a low similarity, yet a similar structure of evolutionarily conserved amino acids residues for catalytic activity between BphC1 and BphC2 was observed.